In serum, sTWEAK levels positively correlated with sCCL7 and sCXCL5, and it is known that high expression of CXCL5 is closely related to cancer progression [34–36], which is in line with the association we observed in our cohort between PSA levels and sCXCL5 in urine. Here, CXCL5 is linked to cancer.